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Web apps just happen to have cons for both enterprise and home use. These are however different and not really related.
For enterprise it's maintenance ease. For some reason Windows PC is just too hard to maintain for a typical knowledge worker that uses it at workplace. The PC is however designed around of customization and there's no way around that. So the maintenance burden (upgrades, security fixes, incompatibility) is pushed to IT support. This is not a natural way to handle a PC. Multiplied times hundreds of users times handful of applications its cost becomes unreasonable. So the workaround is too dumb down a PC to become a network terminal limiting the supportable application to a mere browser.
For home use, it's another story. With outbreak of the connectivity, the critical data moved online (to become shareable), and with webapps the principle "put apps where data is" allowing home used apps to be accessible from work has won over better performance.
The maintainability argument still holds here (try a new app without trashing your computer) has a smaller impact. Edited 2010-10-21 18:08 UTC